1. Field of the Invention
The present invention relates to an apparatus for producing an atomic beam. More particularly, the present invention relates to an apparatus for producing the atomic beam, suitable for alignment treatment on alignment layer materials.
2. Description of Related Art
In today's society, highly developed multimedia technology benefits mostly from the advance of semiconductor devices and display units. Among the display monitors, the liquid-crystal display with the superior characteristics of high picture quality, compactness, low power consumption and no radiation has gradually become the mainstream in the market.
The liquid-crystal display mainly is composed of two pieces of substrates as well as one liquid crystal layer in-between. For either the active matrix type liquid-crystal display or the passive matrix type liquid-crystal display, two alignment layers are disposed respectively on both substrates, and the main function of the alignment layers lies in aligning the liquid crystal molecules, causing the liquid crystal molecules to be twisted between the two substrates. The conventional manufacturing procedure of the alignment layer mainly includes two parts: the thin film fabrication and the alignment treatment.
In details, the material of the above alignment layer can be polyimide, hydrogenated diamond like carbon (DLC), silicon carbide (SiC) or SiO2. At present, the alignment treatment of the alignment layer can be classified as the contact type and non-contact type approaches. The so-called contact type alignment treatment usually is performed by rubbing the alignment layer materials. And the non-contact type ion beam alignment treatment is performed by utilizing the atomic beam bombardment with specific tilt angles to the surface of alignment layer.
Regarding the non-contact type alignment treatment, since the energy of ion beam generated by the non-contact type ion beam alignment apparatus is rather high and the ion beam usually can not be completely neutralized into the neutral atomic beam, the alignment layer may easily be damaged. The traditional non-contact type ion beam alignment treatment includes firstly inducing high energy ion beam, and followed by introducing the inert gas for colliding with the ion beam collides to generate low energy secondary atoms. Those low energy secondary atoms bombard the alignment layer materials for the alignment treatment. However, by using this kind of low energy secondary atoms that are generated through the collision of high energy ion beam with the inert gas, the uniformity of the treated alignment layer is poor. Moreover, effective neutralization can not be achieved for the treatment method by converting the ion beam to the atomic beam through charge transfer. Therefore, the traditional non-contact type ion beam alignment treatment can easily damage the alignment layer and deteriorate the quality of the alignment layer. Also, it is most likely to cause uneven alignment for the alignment layer. Nevertheless, if the energy of the ion beam is reduced for alleviating the above issues, the beam current of the ion beam is smaller, thus increasing the time required for the alignment treatment and lowering the yield.